1. Field of the Invention
A lock construction is provided for securely locking the hinged cap for the fill opening of an oil storage tank in the closed position in order as an effective deterrent against unauthorized removal of oil from oil storage tanks.
2. Description of the Prior Art
Oil storage tanks of large volume are conventionally provided with upwarding facing fill or access openings having upstanding flanges extending peripherally thereabout and closure caps are hingedly mounted from the tanks for swinging movement between closed positions closely overlying the flanges and open positions swung upwardly and away from the flanges and disposed to one side thereof. Various structures are utilized for removably locking such caps in closed positions, but conventional locking means have in the past not proven effective against unauthorized persons wishing to take oil from the storage tanks. Accordingly, a need exists for a means by which a hinged closure cover for an oil storage tank may be effectively releasably locked in a closed position.
Various different forms of locking caps and closures including some of the general structural and operational features of the instant invention are disclosed in U.S. Pat. Nos. 1,747,202, 1,778,989, 1,944,535, 4,023,386 and 4,313,321.
However, these previously known forms of locking devices are not specifically adapted for use in conjunction with the oil storage tank closure caps for which the locking cap structural of the instant invention has been specifically designed.